7Demo: String reflecting on mirror,

Print:Supplies:

Warm-Up ExerciseCurrently in the classroom, find an

object that isOpaqueTranslucentTransparent

Agenda

1. LESSON: Mirrors, Law of Reflection, Magnification

2. Classwork

Review

.

Angles in Mirrors

• the incoming ray

Incident ray

• The angle between the incident ray and the normal

Angle of Incidence

• the dotted, imaginary line • At the point of reflection• Perpendicular to the mirror

Normal Lines

• The angle between the reflected ray and the normal

Angle of Reflection

Law of Reflection•The

angle of incidence is always equal to the angle of reflection

The Law of Reflection states:

Rules for Drawing Plane Mirrors

Images in the Mirror What is the distance from the mirror to

the Virtual Image? How are the images different?

Complete the Diagram Below Demonstrating Mirror-Reflections

WORD

Complete the Diagram Below Demonstrating Mirror-Reflections

Science

See folding paper trick…

Reflections using Mirrors The line of sight principle

in order to view an image of an object in a mirror, a person must sight along a line at the image of the object.

How many people can be seen in the mirror by: A? B? C?

WARMUPDraw the reflection of light rays on the plane mirror. Use normal lines to guide your work

Curved Mirrors

Draw the light rays from the source

Positions on Curved Mirrors

•a point where light rays meetFocal point (F)

•Centre of the sphere of which the mirror is a part.

Centre of curvature (C)

•middle part of a curved mirrorVertex (V)

•A line passing through F, C and V

Principle Axis

Positions on a Curved Mirrors

•Distance between C and F

Focal length

•Half of the diameter of the circle

Radius

The distance between the vertex and the object is represented by do

The distance between the vertex and the image is di

The height of the object is ho

The height of the image is hi

The focal length (f) is the distance from the vertex to the focal point of a curved mirror

A real image is an image formed by light rays that come from a location of the image.

Curved Mirrors The distance between the vertex and the

object is represented by do

The distance between the vertex and the image is di

The height of the object is ho

The height of the image is hi

The focal length (f) is the distance from the vertex to the focal point of a curved mirror

A real image is an image formed by light rays that come from a location of the image.

Concave Mirrors

Also called a converging mirror, a concave mirror has a surface that curves inward like a bowl.

The closer the object gets to the focal point, the larger the image becomes

Uses for Concave Mirrors Flashlight-to produce a parallel beam

Headlights-to produce a parallel beam of light that can be directed down or straight

Solar Energy http://www.youtube.com/watch?v=qYeynLy

6pj8

Magnification The measure of how much larger or

smaller an image is compared with the object itself.

We can measure it using: Magnification=image height

object height

Distance can be measured the same way: Magnification= Image distance Object distance OR Equation: M= hi

ho

Example Magnification A microscope produces an image that is

5.50 x 10ˉ4 m high from an object that is 2.00 x 10ˉ6 m high. What is the magnification of this microscope?

Solution Equation: M= hi

ho

M=5.5 x 10ˉ4 m 2.00 x 10ˉ6 m =275 The magnification of the microscope is 275

times.

Convex Mirrors Mirror with a

surface curved outwards

Convex Ray Diagram

The first ray (red) travels from a point on the object parallel to the principal axis.

The second ray (blue) travels from a point on the object toward the focal point

Class work Pg. 433 #1,2,7,12